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91.
Abstract Despite contemporary inroads made into the textile market by synthetic fibers, cellulose remains one of the world's most important textile materials. This can be rationalized in terms of several factors, the most important of which is the ready availability and continuing supply of this naturally occurring fiber. It has been estimated that vegetation produces about 100 billion tons of cellulose a year [1], and it is partly due to this fact that cellulose has maintained its position and competitive price in world markets. 相似文献
92.
93.
Dr. Benjamin A. Chalmers Hui Xing Sevan Houston Dr. Charlotte Clark Dr. Sussan Ghassabian Dr. Andy Kuo Benjamin Cao Andrea Reitsma Cody‐Ellen P. Murray Dr. Jeanette E. Stok Dr. Glen M. Boyle Carly J. Pierce Stuart W. Littler Prof. David A. Winkler Prof. Paul V. Bernhardt Dr. Cielo Pasay Prof. James J. De Voss Prof. James McCarthy Prof. Peter G. Parsons Prof. Gimme H. Walter Prof. Maree T. Smith Prof. Helen M. Cooper Prof. Susan K. Nilsson Dr. John Tsanaktsidis Dr. G. Paul Savage Prof. Craig M. Williams 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(28):8491-8491
94.
This review discussed recent advancements related to therapeutic peptide engineering. 相似文献
95.
John T. Gupton Alex Shimozono Evan Crawford Joe Ortolani Evan Clark Matt Mahoney Campbell Heese Jeffrey Noble Carlos Perez Mandry Rene Kanters Raymond N. Dominey Emma W. Goldman James A. Sikorski Daniel C. Fisher 《Tetrahedron》2018,74(21):2650-2663
Highly functionalized pyrroles with appropriate regiochemical functionality represent an important class of marine natural products and potential drug candidates. We describe herein a detailed study of the reaction of α-aminoacid esters with vinylogous amides and also β-halovinylaldehydes for the regiospecific synthesis of 2,3,4-trisubstituted and 1,2,3,4-tetrasubstituted pyrroles. Since the vinylogous amides and β-halovinylaldehydes are readily available precursors, rapid access to a wide variety of unsymmetrically substituted pyrroles is accomplished via this methodology. 相似文献
96.
97.
C R Clark C L McMillian J F Hoke K D Campagna W R Ravis 《Journal of chromatographic science》1987,25(6):247-251
An improved liquid chromatographic procedure is described for the quantitative determination of sulindac, sulindac sulfone, and sulindac sulfide from serum. The procedure makes use of acetonitrile extraction of the compounds of interest from acidified serum samples. Under these conditions extraction efficiencies in the 85 percent range are obtained for each of the compounds. The liquid chromatographic separation of the compounds of interest and the internal standard (indomethacin) is accomplished in an isocratic elution procedure using a nitrile (CN) stationary phase. The HPLC separation procedure is completed in less than 10 minutes, giving excellent resolution and peak shape. 相似文献
98.
Reversed-phase liquid chromatographic (RP/LC) procedures are used to optimize the reaction conditions for the large scale preparation of 2,2-dimethyl-N-benzylmalonamide, 1. In acute studies using mice and rats, compound 1 is a very effective anticonvulsant agent. Large quantities of 1 (ca. 300 g) are needed for detailed studies of its chronic effects. LC monitoring of the synthesis of intermediate products and 1 result in the optimum use of reagents, increased product yields, and decreased reaction times. 相似文献
99.
100.
Clark SB Turnipseed SB Nandrea GJ Madson MR Hurlbut JA Sofos JN 《Journal of AOAC International》2002,85(5):1009-1014
A confirmatory method is described for phenylbutazone (PB) residues in bovine kidney tissue. Ground kidney tissue is diluted with water, and the mixture is made basic with 25% ammonium hydroxide in water; the lipids are extracted with ethyl and petroleum ethers. The ether layer is discarded, and the tissue is acidified with 6N HCl. PB residues are extracted with tetrahydrofuranhexane (1 + 4). The extract is passed through a silica solid-phase extraction column, and the eluate is evaporated to dryness. The residue is dissolved in acidified acetonitrile-water-acetic acid (50 + 49.4 + 0.6). A single quadrupole mass spectrometer coupled to a liquid chromatograph with an electrospray interface is used to confirm the identity of the PB residues in the kidney extract. Negative-ion detection with selected-ion monitoring of 4 ions is used. Sets of control and fortified-control kidney tissues (at 50, 100, and 200 ppb PB) and several kidney tissue field samples were analyzed for method validation. The method was tested further during the course of a survey to determine the incidence of PB residues in bovine kidney samples obtained from slaughterhouses across the country. In addition, the method was tested for use with an ion-trap mass spectrometer coupled to a liquid chromatograph, which allowed confirmation of PB at lower levels (5-10 ppb) in kidney tissue. 相似文献